Morbidity and mortality of human newborns remain significant public health concerns. Streptococcus agalactiae or Group B Streptococcus (GBS) cause invasive infections such as pneumonia, sepsis and meningitis in human newborns. Moreover, GBS are a significant cause of in utero infections leading to preterm births and stillbirths. We recently showed that the pluripotent toxin important for GBS infections is an ornithine rhamnolipid pigment also known as granadaene. The pigment/lipid toxin is cytotoxic to a number of host cells and induces a proinflammatory immune response. The objective of this proposal is to understand how the pigment causes host cell lysis and induces an immune response and to also define how pigment mediated activation of host cells affects GBS colonization and infection-associated preterm births.